With development of network technologies, network virtualization and network centralized control gain more attention, and are widely applied. Virtualization may be understood as a resource management technology. Various physical resources of a computer, such as a server, a network, a memory, and a storage are abstracted, converted, and then presented. In this way, a barrier that a physical structure and a function are inseparable can be broken, and a user may use these resources in a manner better than an original configuration, without excessive restrictions from physical hardware.
In a network using a virtualization technology, traffic flow forwarding is presented to a user in a virtual network element form. Further, a virtual network element may include multiple physical network elements, or in other words, a virtual network element may be obtained by virtualizing multiple physical network elements. When an original forwarding path of a traffic flow needs to be modified in a virtual network element due to a service requirement (for example, Internet Protocol (IP) Security (IPsec)) monitoring needs to be performed on the traffic flow), a redirection path may be deployed on the virtual network element to ensure normal processing of the traffic flow.
However, in some other approaches, when a redirection path of a traffic flow is to be deployed inside a virtual network element, a configuration parameter of each physical network element needs to be separately configured inside the virtual network element according to a topological relationship inside the virtual network element (for example, an IP routing table of each physical network element needs to be modified) in order to determine the redirection path. In this way, a packet of the traffic flow can be forwarded along the redirection path. This static configuration manner of a redirection path requires professional technical personnel to spend a large amount of time to complete, and a workload is heavy and a process is complex.